AIDS is described as a viral infection and pandemic. What is often cited as its cause in the material?

• A. Bacterial infection
• B. Modern lifestyles
• C. Genetic mutations
• D. Air pollution

Answer: (B)

The main idea here is that AIDS is caused by a virus, HIV, and its spread is tied to social and behavioural factors in the modern world. In the material, the focus is on how conditions of modern life—like increased travel, dense urban networks, and risqué or unprotected sexual behaviours, along with practices such as sharing needles—facilitated rapid transmission. This makes modern lifestyles the best description of what the material cites as the cause of AIDS’s spread, even though the biological cause is the HIV virus itself. The other options don’t fit the material’s emphasis, since AIDS isn’t described as caused by bacteria, genetic mutations, or air pollution.